1. Technical Field
The present invention relates to a robot provided with a jointed arm having a plurality of joints.
2. Related Art
In recent years, the movement toward automating the operations that had been performed by a worker on an object to be worked on by introducing a robot provided with a jointed arm in an assembly line has become active in manufacturing industries. For example, JP-A-2007-118177 (Patent Document 1), as the above-described robot discloses a dual arm robot provided with jointed arms, each being formed of a plurality of arms joined by a joint mechanism, the jointed arms provided on both sides of a body which is supported on a base and is rotatable with respect to the base. Such a robot performs an operation in accordance with an end effector attached to the tip of the jointed arm on an object to be worked on which is placed in a working space of the robot.
Incidentally, the range of operations performed by the worker in the assembly line is often not 300 mm or more away from the worker. In addition, since such operations are often performed by the robot, the jointed arm is often folded so that the end effector of the jointed arm is located close to a robot main body. On the other hand, in the robot described in Patent Document 1, to move the end effector close to the robot main body, the joint mechanisms have to jut out toward the side of the robot main body, not being stacked in layers in front of the robot, in the jointed arm. As a result, to avoid a collision between the jointed arm and the outside every time the robot performs the above-described movement, it is necessary to increase the size of the space on the side of the robot main body, the space in which the robot is operating.